Duke1978

My temperature gauge is not reading any temperature it is spiked to
the left. How do you check the temperature gauge? I know the
problem could also be the sending unit. How do you check the sending unit?

Is it possible to also have a bad thermostat that is causing the issue?

JohnZ

With the key in the "on" position, remove the connector from the sending unit, and the gauge should peg to full cold; then touch the terminal in the connector to the engine, and the gauge should peg to full hot. If it works that way, the gauge is OK.

To check the sending unit, use your VOM/Multimeter (set to Ohms); at room temperature, you should see about 500-600 ohms resistance between the center terminal and the hex portion. At normal engine operating temperature (180*F), you should see about 125-150 ohms.

Duke1978

Thanks

Duke1978

Thanks

Duke1978

Can the temperature sending unit for a 1960 be rebuilt?

stratplus

Just go down to AutoZone and pick up a Wells TU-5 for about 6 bucks.

Duke1978

What the best thing to use for sealing the threads? I read that certain
things can effect the temperature readings.

Donald #31176

Not necessary. When buying your TU-5s buy about 6 of them. Then test them for proper calibration in a pot of 180* H2O . Return the rest that do not meet specs.

jim lockwood

Not true. The threads are tapered and will wedge themselves tightly against the intake manifold threads, making an excellent electrical contact.

Duke1978

So when you take them out of the water you attached them to the
cable, turn on the key to on and check the gauge correct? I also
assume that the sending unit needs to be touching the engine block,
is this also correct?

Thanks

Donald #31176

Using an ohm meter attach one lead to the top tip of the sender and the other lead to the hex portion while the sender is in the 180* water. The sender is calibrated to your gauge if the impedance is within the 125-140 ohms.

Duke1978

I replaced my Temperature sending unit and thermostat in my 60 vette. The temperature reads at 200 degrees in a very short period of time and hovers between 180 - 220 degrees on the gauge. Is this
normal?

Duke1978

I replaced my temperature sending unit and thermostat on my 60 Vette and the temperature reads 200 degrees in a few minutes of driving. The temperature stays at between 200 and 220 degrees. Is this normal?

Frankie the Fink

I would say no...my stock '61 270hp car has a 160* thermostat and runs at about 165*-175* on the road with excursions to 185*-195* at a long idle at stop lights.
I think that's pretty normal.

LB66383

OK, but I gather from this that you are still not sure if the sending unit and the gauge are compatible. The actual temp could be much different. Get/borrow an infrared temperature gun. Aim it at the top radiator hose where it connects to the thermostat housing, and see what temperature that tells you. Compare that to the temp gauge to determine how accurate your gauge is reading. If it's really running around 220*, then there are other issues.